Join the Globe at Night Count

How many stars can you spot with the lion’s perch?

By J. Alex Knoll

This next week marks the last of this year’s Globe At Night citizen-science sessions, where ordinary folks like you and me lend an eye observing the night sky. This month’s target is the constellation Leo. Armed with a star chart downloaded from the group’s website, backyard astronomers count how many stars they can spot. You can submit results — from one or more locations — thru the 20th.
Collectively, the data mined from the Globe At Night program are used to help astronomers gauge the sky’s darkness and the effects of light pollution around the world. Nearly 10,000 people sent in reports during the February and March sightings. They’re aiming for a grand total of 15,000, so your support is crucial. Join in at www.globeatnight.org.
With its head and mane appearing as a backward question mark, Leo is one of the most easy-to-recognize constellations. It appears in the east with sunset, and by 10pm the lion is high in the south. You’re likely to first spot the red glow of Mars, nestled a few degrees from the constellation’s brightest star, Regulus. But that’s an added bonus, as planets don’t count in your Globe At Night tally.
It will take at least 15 minutes for your eyes to adjust to the darkness, over which time more and more stars will come into view. Once your night-vision is set, and you think you’ve spotted all you can, try looking askance from the corner of your eyes. You’ll be amazed how many more stars you can see — at least a magnitude’s worth! Looking straight ahead, our eyes rely on cone cells, which are ideal for discerning color, depth and focus — under bright light. Using our peripheral vision, however, our eyes rely on the more light-sensitive rod cells, which register only black and white.